Early settlers were all of German or Alsatian descent and of the Roman Catholic faith. John B. Kroetsch built the first sawmill in the 1850s.

The place was first named Stoney Creek for a small creek running through a rocky bed. When a post office was opened, the residents applied for the name St. Marys, but another place of that name existed.

The unlikely alternative was Formosa, a Portuguese word meaning 'majestic,' and the former name of what is now Taiwan.

A brewery was founded in 1869, and the workers remained independent of trade unions through the 1950s and 1960s when major Ontario breweries were suffering long strikes.

The resultant shortage of beer brought long lineups of thirsty customers to Formosa Springs Brewery, which then operated around the clock.

In 1901 exploratory drilling for oil tapped into a gushing well from which pure, sparkling water still flows. Between 1875 and 1883 the huge, Gothic-styled Church of the Immaculate Conception was built.

. It was designed by Joseph Connolly of Guelph and has fme stained glass windows and five decorative carvings.